This invention relates to the field of housings for electrical and control devices. More particularly, the present invention relates to a device housing assembly for both an electrical device, such as a switch or a receptacle, and a control device, such as a relay, for controlling the electrical device, the device housing assembly providing a barrier between high and low voltage wiring.
In recent years there has been an increasing demand for apparatus for controlling electrical devices such as receptacles and switches from a remote source, such as a computer or a microcontroller as well as for means for determining whether a remote electrical appliance, such as a lamp, is on or off, and providing such information back to the computer or microcontroller. For example, remote control of a switch or receptacle can permit lights to be turned on or off in a programmed sequence. By use of remote control, the power available at a receptacle may be varied so that a lamp plugged into the receptacle may be dimmed from a remote source.
There are many uses for remotely controlled devices in the area of energy conservation. For example, by monitoring exhaust fans in a building to determine which fans are running, a computer can control the fan based upon the time of day or other information so that the fan does not run in an unoccupied building.
Conventionally, remote control of receptacles and switches has been accomplished by the use of radio or infra-red frequencies to pass information to and from electrical devices, such as receptacles or switches. The controlled device is manufactured with electronic components contained within the device. There are limitations to this type of device. Interference from other radio systems may cause devices to switch on or off unpredictably. Interference from neighboring electrical devices may cause unpredictable results. Infra-red requires a xe2x80x9cline of sightxe2x80x9d to the device and is therefore also limited.
Another system for remote control of electrical devices uses the AC power lines as a carrier and superimposes a controlling signal at a high frequency. This method also has limitations. For example, when lamps are switched on, this system may not be able to switch them off because the temperature change at the lamp may cause interference. Further, there are problems in trying to control fluorescent lamps with this system and discharge lamps or halogen lamps cannot be controlled.
The control systems discussed above all use manufactured modules providing an electrical receptacle into which the controlled device is plugged, the module in most cases plugged into an existing receptacle to receive power. These remotely controlled devices are surface mounted and may be unattractive to look at, expensive, and are provided in limited styles and colors, which may not match the decor of their surroundings.
It is desirable to provide a controlling system that makes use of existing receptacles and switches and which can control such devices while they are mounted within an electrical box in the normal manner with a cover plate flush with the surrounding wall surface. The installation would then appear to be an uncontrolled outlet or switch, but would be a safer installation as the controlled device could be switched off completely to provide child safety.
For many years there have been reliable systems for providing control of electrical devices by use of low voltage wiring and electronic control devices. When wiring is used to provide control there is less likelihood of interference and most if not all of the limitations of other systems discussed above are overcome. However, since electronic control devices operate at lower voltages than electrical devices such as receptacles, consideration must be given to several parts of electrical codes in existence in many countries which require:
1. When wiring from two systems having different voltages are present in an enclosure, these wires should be physically separate.
2. Wiring must be protected against mechanical damage.
3. Adequate space must be provided in a box which contains an electrical device.
4. A semiconductor device should not be relied upon as a disconnecting means.
5. Terminations for wiring of both systems must be accessible.
Disclosed in the prior technical literature are a number of enclosures for electrical and control devices. For example, Tashjian, U.S. Pat. No. 1,437,324 (Nov. 28, 1922) discloses a combined conduit, junction box and outlet box with a removable facepiece. The conduit/box is divided into high and low voltage portion by a permanent divider. No means for connecting a device in one portion with a device in the other portion is provided. Both portions are accessible when the facepiece is removed.
Haering, U.S. Pat. No. 1,829,648 (Oct. 27, 1931) discloses an electric receptacle baffle for dividing an electrical box into high and low voltage portions. No means for connecting a device in one portion with a device in the other portion is provided and both portions are accessible when the cover plate is removed.
Ohmit, U.S. Pat. No. 3,082,290 (Mar. 19, 1963) discloses a moveable floor-to-ceiling electrical installation for interior of a building comprised of a divided vertical conduit and a divided box joined to the conduit. The conduit and box are divided into high and low voltage portions. Again, no means are provided for connecting a device in one portion with a device in the other portion.
Ceglia, U.S. Pat. No. 3,146,298 (Aug. 25, 1964) discloses an electrical distribution system. Electrical boxes and a bus duct are provided with means for routing wiring from the bus duct to the boxes.
Fork, U.S. Pat. No. 3,701,837 (Oct. 31, 1972) discloses a multiple electrical service underfloor access housing. The housing is divided into portions for high and low voltage wiring with no means for interconnection.
Fork, et al., U.S. Pat. No. 4,323,723 (Apr. 6, 1982) discloses a surface mounted outlet unit with separate compartments with no means for interconnection between compartments.
Bantz et al., U.S. Pat. No. 5,257,487 (Nov. 2, 1993) discloses a floor box for in-floor activations in a concrete floor divided into separate compartments by a partition with no means for interconnection between compartments.
Nattel et al., U.S. Pat. No. 5,354,953 (Oct. 11, 1994) discloses a cable holding device for holding a telephone cable beside an electrical outlet box so that a modular telephone jack can be mount to a faceplate shared with an outlet in the electrical box, but the telephone cable and jack do not enter the electrical box. Again, there is no connection between the inside of the electrical box and the outside space in which the telephone jack is located.
Yetter, U.S. Pat. No. 5,486,650 (Jan. 23, 1996) discloses a partition for dividing a device box. Again, no means are provided for connecting a device in one compartment of the box with a device in the other compartment.
Cottone, U.S. Pat. No. 5,574,256 (Nov. 12, 1996) discloses a recessed transformer electrical outlet box with integral telephone line connection. A cover plate having a modular telephone jack is provided to cover the recessed electrical outlet, the idea being to hide a line voltage adaptor module associated with a cordless telephone base station. No means are provided for connecting the high voltage wiring in the inner compartment of the box with a low voltage device in the outer compartment.
Fabian et al., U.S. Pat. No. 5,594,207 (Jan. 14, 1997) discloses a self-locking divider plate for dividing an electrical box into physically isolated compartments. No means are provided for connecting high voltage wiring in one compartment of the box with a low voltage device in the other compartment.
Lynn, U.S. Pat. No. 5,598,998 (Feb. 4, 1997) discloses an electrical outlet box mounting bracket. The idea is a variant of the Nattel et al. device discussed above.
There is a need, not satisfied by known device housing assemblies for electrical and electronic control devices, for a simple, inexpensive, easy to install enclosure for electrical and electronic control devices that can be flush mounted in a wall and which complies with the requirements of electrical codes.
The present invention is directed in one aspect to providing a device housing assembly for housing an electrical device and mounting a control device in a manner that the high voltage electrical device is separated by a barrier from the low voltage device and so that the electrical device cannot be installed unless the barrier is installed.
The electrical device is of the type having a pair of spaced mounting elements for cooperating with screws or other fasteners and mounting elements on an electrical power outlet box to mount the electrical device to the box. The control device is of the type being connectable to controlled connectors that are connectable to the electrical device to enable electrical communication between the control device and electrical device. The control device is also connectable to controlling connectors that are connected at the other end to a low voltage signal source. When connected, the low voltage signal source transmits a signal to the control device, which prompts the control device to communicate with the electrical device to initiate a desired action.
The major components of the device housing assembly comprise an electrical device housing, a control device housing, and a dividing plate for separating the electrical device and the control device.
The electrical device housing has a first electrical device mounting element at the front of the housing, a front opening at the front of the housing large enough to pass the control device housing therethrough, and, a connector opening elsewhere on the housing large enough to pass controlling connectors therethrough, and preferably at least part of the control device housing therethrough. The connector opening is preferably at the bottom of the housing, but may also be at the top or the side. The connector opening may optionally have side ledges for contacting a pair of flanges optionally locatable on the control device housing.
The control device housing has an opening large enough to pass a control device therethrough. The control device housing has side walls that may be optionally bent over to form flanges along each side of the top opening for locating contact with the optional ledges of the electrical device housing. The outside dimensions of the control device housing are selected to allow the control device housing to be moved through the front opening of the electrical device housing and at least partly through the connector opening and into a position for mounting to the electrical device housing.
The divider plate for completing the electrical device housing comprises an exterior surface adapted for mounting to an offset plate attached to the control device or to the control device directly. The divider plate also has an aperture for passing the controlled connectors therethrough, and a second electrical device mounting element. There are mounting elements for mounting the divider plate to the electrical device housing, such that when mounted, the divider plate covers the connector opening thereby separating the control device and controlling connectors from the electrical device while providing access to the controlled connectors from inside the electrical device housing. When mounted, the divider plate also provides the assembly with a sufficient number of electrical device mounting elements to cooperate with the mounting elements on the electrical device, so that the electrical device can be securely mounted onto or inside the electrical device housing. By locating the second mounting element on the divider plate, the electrical device may not be mounted onto or into the device housing assembly unless the plate is installed.
Means are provided for mounting the electrical device housing to a joist or stud of a wall. Typically in new installations, the electrical device housing is mounted to a joist or stud. Then, low voltage controlling connectors are positioned such that one end is close to the connector opening of the electrical device housing. Then, drywall is installed to complete the wall, leaving an opening corresponding to the front opening of the electrical device housing. Then, the controlling connectors are connected to control device. The control device is then mounted in the control device housing, and the control device housing is mounted to the divider plate. Then, these components are passed through the front opening of the electrical device housing and partly through the connector opening until the divider plate is in place to be mounted to the electrical device housing. Once mounted, the second electrical device mounting element is in place, thereby permitting the electrical device to be securely mounted to the electrical device housing after a power supply and the controlled connectors are connected to the electrical device.
In another aspect, the present invention is directed to providing a housing for an electrical device and a control device for controlling the electrical device, the control device having both controlled connectors and controlling connectors. The housing comprises a body having an access opening for mounting the devices inside the housing and a pair of electrical device mounting elements adjacent the access opening for cooperating with the mounting elements of the electrical device so that the electrical device can be mounted inside the housing. The device housing assembly further comprises a removable divider installable within the body so as to divide the interior of the body into an electrical device compartment accessible from the access opening and a control device compartment. The divider is also provided with attachment elements for attaching the control device to the divider so that the controlled connections are accessible for connection to the electrical device while the controlling connections are accessible for connection in the control compartment.
In another aspect the present invention is directed to providing an housing for an electrical device and a control device for controlling the electrical device, the control device being connectable to both controlled connectors and controlling connectors. The housing comprises a body having a front opening for mounting the electrical device inside the body and one electrical device mounting element. A removable divider installable within the enclosure is provided so as to divide the interior of the body into a compartment to accommodate the mounted electrical device and a compartment to accommodate the control device. The divider has a second electrical device mounting element for attachment of the electrical device so that the electrical device may not be mounted in the body unless the divider is installed. The divider has attachment elements for attaching the control device to the divider so that the controlled connections are accessible for connection to the electrical device while the controlling connections are accessible for connection in the control compartment.
In yet another aspect the present invention is directed to providing a control device module for mounting to an electrical device housing. The electrical device housing is of the type having a front opening large enough to pass an electrical device therethrough, a connector opening for passing a controlled connector therethrough, and an insufficient number of mounting elements to mount the electrical device inside the housing. The module includes a housing for a control device of the type connnectable to a controlled connector and a controlling connector. There is an aperture in a wall of the control device housing for a controlling connector to pass therethrough into the module to connect to the control device, and an aperture in another wall of the control device housing for the controlled connector connected to the control device to pass therethrough out of the module. There is an electrical device mounting element on the housing, and mounting elements for mounting the module to the electrical device housing such that when mounted, the wall of the module having the controlled device aperture covers the connector opening of the electrical device housing thereby separating the control device and the controlling connector from the electrical device while providing accessibility to the controlled connectors from inside the electrical device housing for connection to the electrical device. When mounted, the module also provides the electrical device housing with a sufficient number of mounting elements to mount the electrical device inside the electrical device housing.
A number of optional modifications may be made to or additional elements added to the assembly described above. For example, the assembly may additionally include a clamping plate for clamping an electrical cable against a back wall of the electrical device housing. The clamping plate includes fastening means for fastening the clamping plate to the inside of the electrical device housing. The clamping plate is installed near the top of the electrical device housing and the electrical device housing includes on each side wall a tang bendable inwards to secure the clamping plate in place.
The control device housing may be optionally mounted to the divider plate by means of a nipple and locknut for threading through a suitable sized divider plate aperture.
According to yet another aspect of the invention, there is provided an assembly for housing an electrical device of the type having two spaced mounting elements, and for mounting at least partly outside the housing, a control device for controlling the electrical device and connectable to both a controlling and a controlled connector. The assembly includes an electrical device housing having a front opening large enough to pass the electrical device therethrough; mounting elements on the front of the housing for cooperating with the electrical device mounting elements to mount the electrical device inside the housing; and, a connector opening for the controlled connectors and at least part of the control device to pass therethrough. The assembly also includes a divider plate having an interior surface and an opposed exterior surface adapted to mount the control device thereto, and an aperture for passing the controlled connectors therethrough. The assembly further includes mounting elements for mounting the divider plate to the housing such that when mounted with the divider plate interior surface facing inside the housing, the divider plate covers the connector aperture thereby separating the mounted control device and controlling connectors from the electrical device while providing access to the controlled connectors from within the housing. The assembly may optionally include mounting elements for mounting the assembly to a joist or stud. Preferably the control device housing is mounted to the bottom of the electrical device housing; however, the electrical device housing may be adapted to mount the control device to one of its other walls.